Keto Croque Monsieur. 3.8g carbs for the complete meal.
Hard to believe, right? “Ce n’est pas possible!” I hear you cry. But yes, it’s absolutely possible, with Zero-Carb Sandwich Bread and a super-simple béchamel hack.
And no, it’s not a recipe that means hours in the kitchen, even if you have to make the bread from scratch. It doesn’t take long at all.
So, if you fancy giving a ham and cheese sandwich a ‘posh’ makeover, or are curious to try this famous French dish in ultra-low carb style, I have you covered.
My version of Croque Monsieur is healthier, quicker, and just as good as the original. Minus the carbs.
How to Make Keto Croque Monsieur
First and foremost, you need to bake my Zero-Carb Sandwich Bread, but only half the recipe. Also, you need to bake it as 6 large flat-ish buns, as shown in the photos below.
The second step is to toast 2 buns in a buttered frying pan, one at a time, pressing them while they turn golden. This will take only a few minutes.
Now stir some Dijon mustard into your crème fraîche. And THAT, by the way, is my béchamel hack, my dear readers. Never mind adding time, effort and carbs by making a proper béchamel. Crème fraîche is a worthy keto impostor. Trust me on this.
Yes, yes, je vous entends, mes amis Français. “Croque Monsieur needs béchamel, otherwise it’s not the same dish.” Well, yes, you’re correct. But it tastes almost the same. Plus I have not veered away too much from the French-ness, since béchamel and crème fraîche are both French ingredients 😉
Now all you have to do is to put one toasted bun on top of the other with the gruyère and prosciutto cotto in the middle, and crème fraîche in the middle and on top.
Finish with some grated Parmigiano Reggiano and place under the grill until the middle cheese oozes and the top is a lovely, deep caramel colour.
Et voilà. Prêt a manger. Enjoy!

Keto Croque Monsieur
Ingredients
- 2 bread buns Zero-Carb Sandwich Bread, 1/2 recipe, baked as 6 large, flat buns
- 20 g unsalted butter
- 60 g Gruyère
- 80 g crème fraîche
- 1 tsp Dijon mustard (10g)
- 2 slices prosciutto cotto (50g thin slices)
- 10 g Parmigiano Reggiano
Instructions
- bake the buns for 25 minutes then leave them on a cooling rack while you mix crème fraîche with Dijon mustard.2 bread buns, 1 tsp Dijon mustard, 80 g crème fraîche
- add half the butter to a small frying pan and toast the first bun on both sides, pressing with a spatula to flatten it; repeat for the second bun.20 g unsalted butter
- place a bun (upside down) on your baking tray, top with half the crème fraîche, then prosciutto, then cheese.60 g Gruyère, 2 slices prosciutto cotto
- stack the second bun over it (upside down again), spread the remaining crème fraîche right up to the edges and slightly over (to avoid scorching) and top with Parmigiano Reggiano.10 g Parmigiano Reggiano
- slice your tray under your oven grill (not too close), set at 200 °C: your croque monsieur will be ready when melted cheese oozes and the top has developed golden spots.
- best served immediately.
Notes
Nutrition
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This French makeover of the humble ham and cheese sandwich is easier than you might think, with my béchamel hack.